Are teens fleeing Facebook or not?

More people are using Facebook. And they're using Facebook more. The social networking site's number of monthly users has jumped 21% year over year to 1.5 billion in June; 61% of those people logged on every single day. Not surprising then that, as Facebook's robust ads business gains momentum, the firm's stock price has finally shot above its $38 initial public offering debut. But what's going on, then, with teens? For the better part of 2013, reports have been rippling through the media that fickle youngsters are deserting the service. These reports trickle up through anecdotes as analysts, editors, and engineers study their children's Facebook behavior. CEO Mark Zuckerberg denies it.